The given expression is
-2x² + 17 - 15x + 7xy
The algebraic expression may be written as
-2x² + 7xy - 15x + 17
The constant term does not contain either x or y.
Therefore 17 is the constant term.
Answer: 17
There are 4 US quarts in a gallon.
Hope I helped!!!! :)

Let,
- Mass of the steel be 108x
- Mass of the copper be 7x
- Then, Total mass = 108x + 7x = 115x
Given,
- Total mass of the coin = 230 mg
That means,
⇛ Total mass of the coin = 230 mg
⇛ 115x = 230 mg
⇛ x = 230 mg/115
⇛ x = 2 mg
Then,
- Mass of the steel = 108(2) = 216 mg
- Mass of the copper = 7(2) = 14 mg
☁️ ANSWER - 14 mg (Mass of copper)
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